Water changes

[dhvService]

Look, this really is not hard to understand. Nothing appears in your tank by magic.
If all that is ever being added to the tank is fish food, then everything that grows in that tank grows from the nutrients provided by the fish food.
There is no magic, only boron, carbon, calcium, copper, iron, magnesium, manganese, molybdenum, nitrogen, phosphorus, sulfur and zinc.
Measure the amount of nutrients being added, subtract those consumed by fish and plants, and what is left over is excess nutrients. The excess nutrients accumulate in the water and can be measured. When the accumulation reaches significant levels, a water change is the most effective treatment.
The goal for some of us is to monitor this cycle, and not over feed or overstock so that the supply of nutrients meets the demand for the nutrients.
If there is anything in the tank that appeared by magic, then I will evoke the same magic to remove it.

Has anybody ever told you just how beautiful you are when you are wrong? :naughty:

A fish is what it eats. It is the total sum of every meal it ever ate. And so are you. And so is your tank.

 

[dhvService]

Lol...linky please....have you ever studied old tank syndrome??

Here is the scoop. This comes from "Freshwater Aquarium Chemistry" which is an excellent book written by Kevin J Ruff, PHD.
"As mentioned earlier, the buffering capacity of your aquarium will slowly increase over time, especially if you adjust pH frequently. If you're always adding sodium bicarbonate and monobasic sodium phosphate without removing any of them, they will become more and more concentrated. Compounds that have multiple equilibria, like the ones you add to adjust pH, produce a buffering effect, and as they become more concentrated, the water's capacity to buffer will increase. Remember to periodically perform water changes to reduce the buffering capacity so that any pH problems you do experience will be much easier to correct."

I can see how both of us are displaying credible information. One assumes pH manipulation is performed and the other is without. But I would like to study this further so I understand it completely.

In regards to the "old tank syndrome", although he does not call it that, he talks about disturbing the waters buffering capacity with a large water change causing a sudden swing in the pH, either releasing ammonia that was previously bound to calcium raising the pH were the ammonia is more toxic to the fish. I am still not clear on this, more study is needed here as well. Thanks for you input.

So far the score is... Water change indicators are nitrogen and buffering capacity and pH. A failed buffering capacity seems to be the most likely to cause instant destruction.

 

[Rbishop]

“The hallmark of a Low-tech aquarium is that it is easily maintained. Aquariums seem to do well without hobbyist adjustment, maintenance, and cleaning. For example, my own aquariums often go for six months or more without water changes. Fish get fed well, so that plants do not need to be fertilized artificially. The only routine maintenance is replacing evaporated water and pruning excess plant growth. Tanks that are unbalanced need constant cleaning and adjustment.”


Excerpt From: Diana Louise Walstad. “Ecology of the Planted Aquarium.” Echinodorus. iBooks.
This material may be protected by copyright.


Check out this book on the iBooks Store: https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=661029773

I would wager 95% or more of all tanks out there wouldn't even begin to equal a Walstad tank....professing and favoring frequent water changes to maintain the balance is the easiest hobbyist method to do.

 

[huapala]

You guys are all off topic, if you want to talk about over populating and over feeding tanks, start your own thread. Thank you.

how is this off topic dude? you better re-read the title of this thread then re read the OP's questions.

Sent from my VS920 4G using MonsterAquariaNetwork App

 

[Slappy*McFish]

Over-crowding and over-feeding is indeed relevant to the discussion here.

 

[THE V]

You'll need to measure multiple things in order to scientifically determine what the exact time is optimal to do a water change: TDS, pH, EC, KH, NO3, etc. It might be that your tank only needs replenished every year or so. That being said do you have all of the equipment to test for it?

Water changes are preventative maintenance and help keep the water chemistry stable. Most of the time when you do a water change the tank doesn't really need it. But the routine keeps thing from building up and causing issues. Since people with all levels of knowledge and skill level are keeping fish it is generally best to use the K.I.S.S. principle. What could be simpler than "Do X% water change every week to keep your tank healthy".

I dose ferts in my tank so I'm naturally concerned with the salts. I do around a 75% water change every week so that when I'm away for a month the water chemistry barely changes.

 

[FishFanMan]

I'm really glad we're have a great discussion on such a basic topic as a WC. I began to think about WCs because I'm starting a new Spec V tank for my 1 betta and 6 CPDs and plan to add AquaBella to cycle this tank. Since AquaBella has denitrifying bacteria that converts nitrates to nitrogen gas nitrates should be very low as a result. I have confirmed this in my main tank until recently when I treated the whole tank with General Cure which might have hit these bacteria pretty hard so I now see nitrates in my main tank. (I will add AquaBella to my main tank also as it treats about 50 gallons).

As for my main tank, I do add liquid CO2 every day and weekly Flourish ATM which I may slow down since my plants are getting really big now. I'm not overfeeding my fish and params are great and my pH is steady at about 7.4 (I did try to lower it but gave up after adding lots of pH down by API with no effect). I think I do agree that as the tank ages, the buffering capacity increases (should have more ionic compounds in it versus tap, RO/DI/distilled has none) so that's good as long as it is at the pH we want.

Since my nitrAtes are good, I have been using TDS until recently to do a WC. I've started an algae scrubber about 2 months ago and this has stabilized TDS to a constant 160 which is in the range I'm shooting for for my dwarf rams and neon tetras. Since the TDS and nitrates are not increasing, I'm at a loss to know when I should do a WC. If the nutrients from the ferts that I'm adding is starting to build up, I thought it would show up in the TDS measurement. It used to but with the scrubber, the algae growing in there seems to be taking care of that.

So I'm still struggling to find some test/measure of something to tell me I should do a WC.
Today I use these measurements to determine water quality, if any are out of norm then I do a WC.
1. 3 of the main params
2. pH
3. TDS/Conductivity
4. GH and KH

What else is out there to check?

 

[FishFanMan]

V, these are what I use to monitor my tanks.




And from my G6 is the conductivity reading (spike is from the General Cure, ugh!)


And this is my new Spec V, cloudy with good bacterial bloom (I haven't added AquaBella yet, I'll do it once it's clear). Yeah I added extra LED lights on the left had side (couldn't resist clearance items at Pets Supplies Plus!)

 

[fishorama]

I've lived with hard water & more lately with soft. With hard water GH & pH would climb with only top ups. In soft, my KH would drop to 0 & my pH drop a lot in as little as a week. I never used to test for KH before soft water & had some problems. Both were in moderately planted tanks, probably what most would deem heavily planted but fairly slow growers, mostly. Plants "use up" KH, & then there's the whole "seasonal" water most all of us have, where ever you live..

The "Walstad" method involves very heavily planted tanks & very low fish loads & some of her theories are just not proven. You can find almost anything to support or disprove any theory with varying amounts "facts". Your tank is very lightly planted with slow growers.

 

[mesto]

What we are discussing are triggers to determine when a water change is necessary. We have been discussing this from a nutrient perspective. What are your concerns?

I have to add nitrates so my plants don't develop nutrient deficiencies. I still consider weekly water changes (every 2 weeks at worst) critical to maintaining my tanks in a stable condition good for fish and shrimp.

If you got a total dissolved solids (TDS) meter you would see your TDS in a tank with no changes going up and up due to evaporation. Pure water evaporates out but whatever was dissolved in that water (salts, ions etc) will remain and increase in concentration. When you top off you are adding still more salts unless you use distilled water (which has its own problems). TDS is often as important, if not more so, than pH.

The second reason I consider water changes good practice is organic compounds released by the fish (hormones etc) that build up in the water. Purigen may take care of some of this.

All my fish and shrimp in all 3 of my tanks love water changes. They swim into the water as I pour it in and are active and nicely colored after a 50-70% WC.